I want to alert you to a couple of recently published bird books from Princeton University Press.

The first is “The Crossley ID Guide to Raptors.” This book follows the format of Richard Crossley’s well-received “ID Guide to Eastern Birds.” The Crossley guides use photographs rather than paintings or drawings to illustrate the birds. For each species, a composite plate with many images superimposed on an appropriate landscape is presented. This guide contains 101 photographic scenes with 35 double-facing. Brief, dense text on identification is provided at the bottom of each plate.

The new raptor guide is co-authored by Jerry Ligouri and Brian Sullivan. Ligouri has published a raptor field guide of his own and both men are expert in raptor identification.

To really develop confidence in identifying a bird species, you need to master five views: from above, from below, from head on, from tail on and from a lateral view (left or right). Crossley and colleagues make sure that views of all of all these perspectives are provided for each raptor. Of course, the plumage of young raptors differs from adults; these different plumages are well covered along with geographic differences. The authors devote five plates to the red-tailed hawk and three to the rough-legged hawk.

The book contains 81 photographic plates. The last third of the book provides an account of each species, including a large map of the distribution of each species. Each account follows a consistent format with sections called Overview, Flight Style, Size and Shape, Geographic Variation, Molt, Similar Species, Hybrids, Status and Distribution, Migration, and Vocalizations.

An extremely useful feature of the book is a collection of mystery photos. The authors provide a number of composite plates to test the reader’s identification skill.

For instance, one plate gives a number of eagles in flight; a reader needs to decide if each is a golden eagle or a bald eagle. Similarly, one plate pictures 21 accipiters at all different angles. The challenge is to decide if each is a sharp-shinned hawk or a Cooper’s hawk. A key is provided for each plate, giving the species, age and sex of each mystery photo and a brief explanation. These plates are powerful learning tools. From my experience, they will also give you a generous piece of humble pie.

Thirty-four species are covered, comprising two species of New World vultures, six falcons, and 24 hawks, eagles and kites. The book measures 10 by 7.5 inches so is really not convenient to carry in the field. Use it as a learning resource and refer to it often.

The second newly published book is “The World’s Rarest Birds” by Erik Hirschfield, Andy Swash and Robert Still. The scope of the book is based on the Red List of Birds maintained by the International Union for the Conservation of Nature (IUCN). The IUCN Red List is considered to be the most scientifically objective system for classifying species in terms of their risk of extinction. The Red List incorporates six levels of concern, and this new book covers the 197 species listed as critically endangered and the 389 listed as endangered.

The book begins with a description of the types of threats on Red-Listed birds. These threats include geological events, fishing, damming, pollution, energy production and mining, climate change, logging and agriculture/aquaculture.

The coverage of the species accounts is geographic with the world divided into Europe and the Middle East; Africa and Madagascar; Asia; Australasia; Oceanic Islands; the Caribbean, North and Central America; and South America.

Four species are covered on each page with a color photograph, a distribution map, an estimate of population size, a listing of threats to the species, and a short paragraph on the biology and population changes. Scattered throughout are descriptions of threatened species hot spots. This fine book is simultaneously fascinating and saddening. 

Herb Wilson teaches ornithology and other biology courses at Colby College. He welcomes reader comments and questions at:

whwilson@colby.edu